聚合物驱波及系数和驱油效率实验研究

Experimental research on sweep efficiency and oil-displacement efficiency of polymer flooding

通过室内三维物理模拟驱油实验,研究了非均质砂岩油田聚合物驱油过程中波及系数与驱油效率的变化特征,探讨了采用聚合物驱工艺的储层类型对提高采收率的贡献程度。结果表明,在有隔层的条件下,中渗透层贡献程度达到了48.35%;其次是低渗透层,贡献率为30.86%;而高渗透层仅为20.79%。聚合物驱的主要作用在于提高中、低渗透层的波及系数。与注水工艺相比,聚合物所具有的粘弹性能提高驱油效率,但其对提高采收率的贡献是有限的。

The characteristics of sweep efficiency and oil-displacement efficiency during the polymer flooding in the heterogeneous sandstoneoilfield were studied by oil-displacement experiments on three dimensional physical models. The effects of reservoir type with polymer flooding technology on enhanced oil recovery were analyzed. When the barrier exists,the contribution of medium-permeability reservoir to enhance oil recovery is 48.35%. The low permeability reservoir has a contribution of 30.86%,and the high-permeability reservoir has 20.79%. The analysis shows that the polymer flooding is dominant to improve the sweep efficiency of reservoirs with low and middle permeability. Comparing with water flooding,the viscoelasticity of polymer flooding is favorable for improving the sweep efficiency of reservoirs, hut it is limited to enhance oil recovery.